Fangtastic Facts
Photography: © Lauren Suryanata / Shutterstock
White-Lipped Island Pit Viper
(Trimeresurus insularis)
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The white-lipped island pit viper (Trimeresurus insularis) is a great example of colour diversity within the same species. Depending on its location, it may be yellow, green, turquoise or even blue, like the morph shown above.
Description
It has a broad, triangular head that is clearly distinct from the neck. Its slightly keeled scales enhance climbing, aid burrowing, and diffuse reflected light to improve camouflage.
It has large eyes with vertical pupils, and the iris colour ranges from gold to bronze or reddish tones.
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As a pit viper, it has a pit on each side of its face, between the eye and nostril, which it uses to detect heat from warm-blooded prey.
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The scales along its lips are typically whitish, which gives the species its name.
The tip of its tail often displays a contrasting red, orange, or pinkish tone.
Adult females typically reach an average size of around 81cm, while males reach around 60cm in length.
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Important: Colour, markings and overall appearance can vary considerably between individual snakes. Photographs, descriptions and information on this website should not be relied upon to identify a potentially venomous snake. If you encounter a snake, keep your distance and leave identification and removal to trained professionals.
Green coloured white-lipped pit viper (Trimeresurus insularis) on a branch. Photography: © Lauren Suryanata/Shutterstock
Yellow‑coloured white‑lipped pit viper (Trimeresurus insularis) in an S‑shaped pose, displaying its characteristic reddish tail tip. Photography: © Kurit Afshen/Shutterstock
Distribution
The blue morph is mostly restricted to Komodo Island; however, it can also be found in other areas of Southeast Asia, where other colour morphs of this species are found.
Habitat
This species is typically found in monsoon forests and, less frequently, in agricultural areas and bushlands. It is primarily arboreal and spends most of its time in trees.
Diet
Its diet consists mainly of birds, small mammals, and frogs. The species is primarily nocturnal and hunts at night.
Reproduction
This species usually lives for 9 to 11 years. Its mating behaviour is similar to other vipers and includes male combat, courtship, and a seasonal readiness to reproduce. Trimeresurus insularis is ovoviviparous, meaning females retain the eggs internally until they hatch, resulting in the birth of fully developed live young rather than external eggs. Most litters have 7 to 17 newborns; however, litter size varies by individual and island population. Births often occur at the beginning of the rainy season, when conditions and food are best for the young to survive.
Venom
Trimeresurus insularis venom contains several important toxins, including snake venom metalloproteinases (SVMPs), snake venom serine proteases (SVSPs), and phospholipases Aâ‚‚ (PLAâ‚‚s). These toxins can interfere with blood clotting and harm blood vessels and tissues, which may lead to bleeding, swelling, tissue death, small blood vessel damage, inflammation, and pain.
Conservation status
Although the blue morph is uncommon, the species as a whole is classified as least concern because of its wide distribution and the absence of significant threats.
Fangtastic Fact
The blue morph keeps its bright blue colour for its whole life, and individuals do not change colour as they grow. This differs from some other snake species that only show certain colours briefly, such as juveniles with bright patterns that fade as they become adults, or species that change colour with the seasons or when stressed.
Disclaimer
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Content on this website is provided for general educational purposes and is not suitable for identifying snakes or guiding interactions with them. While reasonable care is taken to ensure accuracy, no guarantee is made regarding completeness or suitability for specific circumstances. Wild snakes should not be approached or handled, and professional snake catchers should be contacted if assistance is required. By using this website, users acknowledge and accept these terms.
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